System of electric-current distribution



April 21, 1925.

v C. A. TURNER SYSTEM (5? ELECTRIC CURRENT DISTRIBUTION Filed Sept. 25, 1922 INVENTOR.

ATTORNE neutral conductor thereof.

Patented Apr. El, 1925.

- il STATES insane CHARLES A. TURNER, GI CHICAGO, ILLINOIS, ASSIGNOR 'IOv GISHDLT MACHINE GOM- PANY, OF MADISON, WISCONSIN,

A CORPORATION OF WISCONSIN.

SYSTEM OF ELECTRIE-CURRENT DISTRIBUTION.

Application filed September 25, 1922. Serial No. 590,277.

To all 1071 am it may concern Be it known that 1, CHARLES A. TURNER, citizen of the United States, residing at Chicago, in the county of Cook and State of Illinois, have invented a certain new and useful Improvement in Systems of Electric- Current Distribution, of which the following is a'full, clear, concise, and exact de scription.

My invention relates to systems of electric current distribution having means for supplying current to translating devices at low voltage from circuits furnishing current to other translating devices at high voltage, and particularly to such systems that are covered by my Patent 1,402,386, issued January 3, 1922. The system of my aforesaid patent is inclusive'of an electro-magnet, having an armature switch, and a high resistance included in series with this magnet in bridge of the mains, a second electromagnet, also having an armature switch, and a translating device in series with this second magnet and together therewith in parallel with the first magnet, a normally open switch for including the second magnetand the translating device in circuit, a shunv ing resistance element brought in parallel with the translating device and in shunt of the first magnet by the armature switch of the second magnet upon the attraction thereof, and a normally open shunt about said high resistance and established by the armature switch of the first magnet upon the release thereof, there being a current reducing winding in the connection between one terminal of the shunting resistance'and the source of current. Such a system, for example, enables the operation of house bells by current supplied from commercial house lighting circuits.

In lighting systems it is common to groimd one line circuit sideor, if the system is a three \vire system, to ground the This grounding is effected at the generator. Fire under writers rules provide that instruments connected with such a grounded system be not themselves permanently grounded thereat, this precaution being taken to avoid electrolytic action.

The invention has for one of its objects the provision of a grounding switch which applies ground to the voltage reducing instrument while this ilittrument is discos.

nected and which switch serves,'in conjunction with a fuse, to prevent the instrument from being reversely connected with the line or to remain in connection with the line after having once been rightly connected if the mains should thereafter be transposed. The low'voltage circuit that supplies the low voltage translating device is thus guarded against the effects resulting from partial grounds accidentally applied to the side of such circuit that should connected with the ungrounded side of the lighting circuit. I

The invention has for another object the prevention of the operation of the voltage reducing instrument in the event of the opening of the lighting circuit and the transposition of the mains of this circuit in reclosing the same which would bring about a wrong connection of the voltage reducing instrument. In accordance with this feature of my invention the magnetwill become deenergized when the lighting circuit is opened and cannot be energized until the lighting circuit is closed and cannot remain energized if the mains of the lighting circuit are transposed in closing the circuit owing to the blowing of the fuse.

-Means are also provided for further lowering the voltage impressable upon the translating device, whereby a given voltage regulatlng instrument may be employed to enable a translating device requiring lower voltage than the maximum reduced voltage to be supplied from a given commercial circuit.

The accompanying drawing shows the preferred embodiment of the invention, Fig. 1 illustrating the preferred circuit arrangement in its idle condition and Fig. 2 illustrating the system inoperation.

The system that is improved upon will be first generally described, whereafter the relation of my improvements thereon will be set forth.

The supply mains 1 and 2 convey current impressed thereon at the higher pressure, say 100 volts, by the direct current or other generator 3 to supply incandescent lamps 1 or other load. The lamps or other resistance devices 5, 5, connected in series, may, for example, have a resistance of 1000 ohms each. A magnet 6, itself of high resistance but of low resistance with respect to resistance element 5 and of, say 480 ohms,

is included in series with resistances in the same bridge therewith between the mains whereby the magnet is constantly energized, the lamps normally glowing to serve as an indicator of the working condition of the circuit.

The low voltage translating device may be of relatively low or high resistance. The device illustrated incirules a magnet 7, shown as of low resistance, say two ohms, norn-ially partially included in circuit by own armature switch 8 positioned by a. spring 9 in the manner of make and break bells and buzzers to which arrangement the invention is not to be limited. Supply conductors 10 and 11 respectively connect the translating device with the supply mains .l. and 2, and lamps 5, 5 being in the cenductor 11. When the switch or push button 12 is closed, the translating device 7 is completely connected in shunt of magnet 3. Sufficient current continues to flow through magnet 6 to maintain it energized until further instruinentalities operate. A magnet 13, whose winding 1 1 is preferably of the high resistance 01", say, 300 ohms, is in series with the translating device '7 and together therewith in parallel with magnet 6. Ma net. 13 has a normally open circuited resistance 15, say of one-halt ohm, which is in parallel relation with the winding 14:. This resistance preferably, but not necessarily, is also a winding of magnet 13. When switch 12' is closed, winding 14cof magnet 13' is initially energized, armature 16 thereupon. engaging contacts 17 and 18 to close circuit through low resistance 15 to shunt the high resistance winding 14, enough current llowing through windings 14c and 15 to maintain the armature 1G attracted against the force of the armature retracting spring 19. Vhcu the armature 16 is thus attracted a low resistance shunt is established about magnet 6 that includes the shunting resistance 20, say of 4.8 ohms, the armature 16 and contact 17. The resistance of the shunt about magnet 6 that collectively includes element 20, the. armature 16, and contact 17, is sullic-iently high to divert sulticient current through the translating device 7, if this (.evice is of low resistance but whether the translating device be of: low resistance or high resistance, resistai-uze 20 is suiliciemtly low ellectively to shunt the magnet 6. The released armature 21 of this magnet eugaged with its back contact by the spring 22 when the magnet is shunted. When the magnet 6- is shunted its released arimitrure establishes a shunt about the high resistance lamps 5, 5, this shunt including the current reducing resistance element 23, of say twenty ohms resistance, the ariznature 21 and its back contact and the armature 16 of in: net 13 and the front contact: 1'? of this armature. The translating device 7 is now mainly fed through the low resistance element 23 included in the connection between the source of current and one terminal of resistance 20 and preferably in parallel with the high resistance element 5, 5, resistance 2?; being brought into series with the translating device by the released armature 21, the resistance element 20 now jlunctioning to prevent the undue shunting ot' the opcrating current passing through the resistance 22-3 to the translatii'ig device and to reduce the voltage impressed upon the translating device to the predetermined extent.

The vibrating bell 7 may act so sluggish y that the circuit of magnet 13 would be broken and the armature of this n'iagnet retracted from the contacts 17 and 18, while the switch 19 is closcd. l therefore make the armature 16 slow to release by providing the armature end of the core of the magnet 1.3 with a closed copper conductor in accord ance with common practice.

In the preferred embodiment of my present invention, a relay 524-, wound to a hi gh resistance, say 2000 ohms, is included in bridge of the supply conductors 10 and 1t and thereby in bridge of the supply mains 1. and 2 and in series with one of the rcsistance elements 5 included in the same bridge therewith, that said relay is in series with one-half or other selected portion of the combined resistance 5, 5. The armature or armature switch contact 25 ol this relay is connected to that portion oi the relay bridge which is connected directly with the supply com'lm-tm: 10 and the grounded side 1 of the lighting circuit. This armature has a grounded back contact 26 which engaged by the armature 25 through the iustrumentality oi the spri 11g 25' when the voltage reducing instrument disconnected, this contact being so far removed from the core of the relay 24- as to prevent the core from att acting the armature when the armatiuic engages said. contact. In connecting the voltage reducing instrument with the mains, the connectors 27. 28 of the instrument should be respectively connected with the mains 1 and 2, 'whereal ter the button 25 upon the armature is pressed upon to bring the armr'rture within the range of its relay core to hold the armature away from its grouiulcd ba -l: contact. l I? the voltage reducing in;- trumcnt is rcvcrscl wrongly, connected with the line. that is. has its connectors at 2?, 2S mistakenly 1e versed or interchanged, a fuse blowing circui't is established traceable he tron] t grounded generator 3, thivmgh the main 2, the fuse 29 (which becomes blown), instrument terminal 27, the armature to the grounded back contact 26 that is engaged by the armature dinrii'ig the process of cor:- i'iecting the instrument. The wrong cor.- nections have to be reversed and the blown fuse has to be replaced in order to maintain the connection of the instrument with the mains intact.

As a further precaution, the conductor 11 through which the instrument is connected with the line is formed in sections that terminate in the front contacts 30 and 31 of the armature 25. The instrument will be inoperative if it becomes reversely connected with the line due to the transposition of the mains of the lighting circuit following the closing of such circuitafter it has been opened since the fuse 29 would become blown to keep the circuit of the guarding magnet 24 from being closed and thereby preventing the maintenance ofthe continuity of the conductor 11 at said front contacts. The translating device 7 cannot, therefore, be operative until theinstrument has been correctly connected with the line and a new fuse supplied to replace the one that had become blown. The invention may be practiced, however, without the break in the conductor 11 at the contacts 30 and 31.

The system illustrated also includes the fuse 32 in circuit with conductor 11, either or both fuses being blown in the event of the establishment of a short circuit between the instrument terminals.

The resistance 20, when unmodified, establishes a fixed reduced voltage to which the translating device 7 is to be subject. In order that this voltage may be further reduced, I include an adjusting resistance 20 in parallel with the resistance 20. Theparallel connection which includes the resistance 20 desirably also includes the ad justing switch 20 by which variable portions of resistance 20" may be included in parallel with resistance 20 to adjust the voltage to be impressed upon the translating device. This switch may be placed in open circuit position to deprive resistance 20 of its function. This arrangement permits the voltage reducing instrument to adapt the lighting circuit to any suitable translating device which is operable at the maximum reduced voltage or any lower voltage.

lVhile I have herein shown and particularly described the preferred embodiment of my invention I do not wish to be limited to the precise details of construction shown as changes may readily be made without net in abridge of said mains; a second electro-magnet also having an armature switch; a translating device in series with this sec ond magnet and together therewith in parallel with the firstmagnet; a normally open switch for including the second magnet and the translating device in circuit; a shunting resistance element brought in parallel with the translating device and in shunt of the first magnet by the armature switch of the second magnet upon the attraction thereof to de-energize the first magnet; a normally open shunt about said high resistance and established by the armature switch of the first magnet upon the release thereof; a resistance in the connection between one terminal of the shunting resistance and the source of current; a relay in bridge of the supply conductors, this relay including an armature switch having one contact connected with the supply conductor that pertains to the grounded supply main and a grounded complemental contact, these contacts being engageable when this switch is released and a device in the supply conductor circuit between a supply conductor terminal and the corresponding main for rendering the supply conductor circuit inoperative upon reversal of the connections of the supply conductors with the mains.

2. A system of electric current distribution including a source of current; supply mains in circuit with said source of current, one of said mains being grounded; supply conductors provided with terminals for connection with said mains; an electro-magnet, having an armature switch, and a high resistance included in series with this magnet in bridge of said mains; a second electromagnet, also having an armature switch, and a translating device in series with this second magnet and together therewith in parallel with the first magnet; a normally open switch for including the second magnet and the translating device in circuit; a shunting resistance element brought in parallel with the translating device and in shunt of the first magnet by the armature switch of the second magnet upon the attraction thereof to de-energize the first magnet; a normally open shunt about said high resistance and established by the armature switch of the first magnet upon the release thereof; a current reducing winding in the connection between one teiminal of the shunting resistance and the source of cur rent; and a relay in bridge of the supply conductors, this relay including an armature switch having one contact connected with the supply conductor that pertains to the grounded supply main a grounded complemental contact, these contacts being engageab-le when this switch is released, the armature of this armature switch, when re leased, being suficiently removed from the noses-3 5 relay magnet as to be out of the attractive range of this magnet and a device in the suppl conductor circuit between a suppl}. conductor terminal and the corresponding main for rendering the supply conductor circuit intumrative upon reversal of the connections ot the supply coinluctors with the mains.

3. A circuit system including a source of current supply provided with mains, one of which is grounded: two conductors, one be ing coiniected to the ungroundcd main and the second being connected to the grounded main; a fuse in series with said second conductor; a normally open resistance bridge of said conductors including two resistance elements one of which has one terminal connected to said second conductor; a normally open shunt connected across the latter resistance element and. containing a translating device and an operating switch for same; means automatically actuated upon the closing of said operating switch for closing said normally open l'thfltritilllfjl) bridge; a closed brid;g;e oi said eoluluctors including a magnet and means actuated by the deenergizing of same for groundilm said second conductor; a connector in one of said two conductors between said use and the connection of this conductor with said nor mally open resistance bridge said normally open shunt, and said closed bridge; and a connector in the other of said two conductors establishing the connection oil? this latter conductor with said normally open resist ance bridge and said closed ln'id e'c the means for grounding the a'li'oresanl second conductor estalllishing a use blowing circuit through said fuse when contacts 01 both of said connectors are mistakenly interchanged.

In witness whereof, I hereunto subscribe my name this 21st day of September A. i), 1922.

CHARLES A. TURNED 

